Door closer assembly

ABSTRACT

A door closer assembly is provided, including a valve regulating an amount of hydraulic fluid that flows through the valve. The amount of hydraulic fluid flowing through the valve controls a force generated by the door closer assembly on a door. A first sensor measures an angular position of the door, and a second sensor measures an angular position of the valve. The angular position of the valve determines the amount of hydraulic fluid flowing through the valve. A controller controls the adjustment of the valve based on the angular position of the door and the angular position of the valve.

BACKGROUND

The invention relates to the field of door closers, and moreparticularly concerns varying the force applied to a door by a closerdepending on the door operating position.

Door closers are used to automatically close doors, saving people whopass through the doorway the effort of closing the door and helping toensure that doors are not inadvertently left open. In general, a doorcloser may be attached to the top of a door, and a pivotable arm extendsfrom the door closer to a door frame or wall. When the door is opened,the door closer automatically generates a mechanical force that actuatesthe arm, causing the arm to close the door without any manualapplication of force.

Many conventional door closers are designed to apply varying forces to adoor as a function of the door angle, meaning the angle at which thedoor is open relative to the door frame. A door and door closer may beconsidered to experience an opening cycle and a closing cycle. Withrespect to the opening cycle, the door starts in the fully closed orhome position, typically where the door is at the jamb. When the door isopened, the door closer generates little force until the door reaches acertain predetermined door angle, which may be designated as thebeginning of the backcheck region. As the door enters the backcheckregion, the door closer applies force to the door. This force slows theprogress of the door, increasing the force required to open the doorfurther, and may help to prevent the door from hitting a wall orotherwise opening past a desired stop point. Increase in force appliedby a door closer at other points between the home position and thebeginning of the backcheck region may be included as a feature of aparticular door closer. Therefore, as the door angle increases or, inother words, as the door is opened wider, it becomes more difficult tocontinue pushing the door open, usually for protection of an adjacentwall.

When the door is released by the user, for example, from the fullyopened position, the force generated by the door closer begins theclosing cycle. The door may pass through the backcheck region and to thebeginning of a latch region, proximate to the home position, with asubstantially constant force applied by the door closer. As the doorreaches the beginning of the latch region, very little or no force isapplied to the door. If calibrated correctly, the latch region allowsthe door to close without slamming the door or damaging the door frame,and with relatively low risk of injury to a person's body part struck bythe door. Reduction in the force applied by a door closer at otherpoints between the fully open position and the latch region may beincluded as a feature of a particular door closer.

Many conventional door closers are mechanically actuated and have apiston and a plurality of springs and valved ports. The piston movesthrough a reservoir filled with a hydraulic fluid, such as oil. Thepiston is coupled to the door closer's arm such that, as the door isopened, the piston is moved in one direction and, as the door is closed,the piston is moved in the opposite direction. As the piston moves, itdisplaces hydraulic fluid, which may be forced through various valvedports. By allowing, limiting, or preventing flow of hydraulic fluid, thevalved ports control the varying amounts of force applied to the door asa function of door angle. The piston may either cover or exposeindividual ports to make flow of hydraulic fluid through the portspossible depending position of the piston, as determined by the doorangle. The force exerted by the door closer depends on the open orclosed status of the ports.

The door's opening and closing profile can be controlled by adjustingthe valves, which may often be done by turning a screw to alter the flowcharacteristics through the valve and thereby control the force appliedby the closer. However, this adjustment may be problematic in that thevalves interact and changing the setting of one valve generally affectsthe flow rates of the other valves. Many conventional door closersimplement undesirable closing characteristics because installers may beunwilling or unable to manually adjust the valve settings in a desiredmanner, or installers may be unaware that the valve settings can bechanged in order to effectuate a desired closing profile.

Accordingly, there exists a need for a door closer that automaticallyadjusts after initial calibration, resulting in a door motion that hasdesirable opening and closing cycles and is relatively easy to install.

SUMMARY

According to one aspect of the present invention a door closer assemblyincludes a spring; a movable element configured to move in response tomovement of a door, the movement of the movable element loading thespring; at least one gear configured to rotate responsive to a forceexerted on one of the at least one gear by the spring; and a generatorconfigured to generate electrical power responsive to the rotation ofthe at least one gear.

According to another aspect of the present invention a control unit fora door closer assembly includes a spring; a movable element configuredto move in response to movement of a door, the movement of the movableelement loading the spring; at least one gear configured to rotateresponsive to a force exerted on one of the at least one gear by thespring; a generator configured to generate electrical power responsiveto the rotation of the at least one gear; and a printed circuit board(PCB), the PCB comprising an energy storage device and control logic,the energy storage device being charged by the generated electricalpower, the control logic being powered by the generated power andconfigured to control a valve in a door closer, wherein the control unitis configured to be attachable to a door closer.

According to a further aspect of the present invention a method forself-powered operation of a door closer includes providing power to acontrol unit responsive to movement of a door; reading an angularposition of the door; reading an angular position of a valve; andadjusting the angular position of the valve based on the angularposition of the door and the angular position of the valve.

According to a still further aspect of the present invention a methodfor self-powered operation of a door closer includes providing power toa control unit responsive to movement of a door; reading an angularposition of the door; reading an angular position of a valve; andcomparing the angular position of the door to a previously read angularposition of the door; calculating a speed of the door based on thecomparison; predicting a next movement of the door based on thecalculated speed and at least one previously stored calculated speed;adjusting the valve based on the prediction; and transitioning at leastone component of a control unit controlling the adjusting of the valveto a power saving sleep state for a set period of time.

According to an aspect of the present invention a method forself-powered operation of a door closer includes reading a first doorposition and storing the read first door position; reading a second doorposition and storing the read second door position; comparing the firstdoor position with the second door position; calculating a speed of thedoor based on the comparison; associating the calculated door speed withthe first door position and the second door position and storing;comparing the stored door speed with an average speed for the first doorposition and the second door position; and adjusting the angularposition of the valve based on the comparing the stored door speed withan average speed for the first door position and the second doorposition.

According to another aspect of the present invention a door closerassembly, includes a valve, the valve regulating an amount of hydraulicfluid that flows through the valve, the amount of hydraulic fluidflowing through the valve controlling a force generated by the doorcloser assembly on a door; a first sensor, the first sensor measuring anangular position of the door; a second sensor, the second sensormeasuring an angular position of the valve, the angular position of thevalve determining the amount of hydraulic fluid flowing through thevalve; and a controller, the controller controlling the adjustment ofthe valve based on the angular position of the door and the angularposition of the valve.

According to a further aspect of the present invention a system forreduced energy operation of a door closer includes a controller, thecontroller comprising a processor; a voltage storage device, the voltagestorage device being operatively connected to the controller; and agenerator, the generator being operatively connected to the controllerand the voltage storage device, the generator generating a voltageresponsive to movement of a door, the voltage charging the voltagestorage device, wherein the controller enables power to a first sensorto read an angular position of the door only for enough time to insurean accurate reading the first sensor, and wherein the controller enablespower to a second sensor to read an angular position of a valve in thedoor closer only for enough time to insure an accurate reading thesecond sensor.

According to an aspect of the present invention a method for reducedenergy operation of a door closer includes detecting movement of a door;providing power to a controller responsive to the movement of the door;enabling power to a door angle sensor only long enable to obtain anaccurate reading of an angular position of the door and then disablingpower to the door angle sensor; enabling power to a valve sensor onlylong enable to obtain an accurate reading of an angular position of thevalve and then disabling power to the valve sensor; and adjusting theangular position of the value responsive to the read angular position ofthe door and the read angular position of the valve.

According to another aspect of the present invention a controller forreduced energy operation of a door closer includes a timer; and aprocessor, the processor detecting movement of a door, enabling power toa door angle sensor only long enable to obtain an accurate reading of anangular position of the door and then disabling power to the door anglesensor, enabling power to a valve sensor only long enable to obtain anaccurate reading of an angular position of the valve and then disablingpower to the valve sensor, and adjusting the angular position of thevalue responsive to the read angular position of the door and the readangular position of the valve, wherein the controller receives powerresponsive to the movement of the door.

BRIEF DESCRIPTION OF DRAWINGS

For a more complete understanding of the present invention, referenceshould now be had to the embodiments shown in the accompanying drawingsand described below. In the drawings:

FIG. 1 is cut-away perspective view of a door closer assembly accordingto an embodiment of the present invention in position on a door.

FIG. 2 is an exploded perspective view of the door closer assembly shownin FIG. 1.

FIG. 3 is an exploded perspective view of a door closer according to thepresent invention for use with the door closer assembly shown in FIG. 1.

FIG. 4 is an end view of the assembled door closer shown in FIG. 3.

FIG. 5 is a longitudinal cross-section view of the assembled door closertaken along line 5-5 of FIG. 4 with the door in a closed position.

FIG. 6 is a longitudinal cross-section view of the assembled door closertaken along line 6-6 of FIG. 4 with the door in a closed position.

FIG. 7 is a longitudinal cross-section view of the assembled door closeras shown in FIG. 5 with the door in an open position.

FIG. 8 is an exploded perspective view of a valve assembly according tothe present invention for use with the door closer shown in FIG. 3.

FIG. 9 is an inner end view of the assembled valve assembly shown inFIG. 8.

FIG. 10 is an outer end view of the assembled valve assembly shown inFIG. 8.

FIG. 11 is a longitudinal cross-section view of the valve assembly takenalong line 11-11 of FIG. 10.

FIG. 12 is a longitudinal cross-section view of the valve assembly takenalong line 12-12 of FIG. 10.

FIG. 13 is a longitudinal cross-section view of the valve assembly takenalong line 13-13 of FIG. 10 with the valve in a closed position.

FIG. 14 is a longitudinal cross-section view of the valve assembly takenalong line 14-14 of FIG. 10 with the valve in an open position.

FIG. 15 is a longitudinal cross-section view of the valve assembly takenalong line 15-15 of FIG. 10.

FIG. 16 is a perspective view of a drive unit according to the presentinvention for use with the door closer assembly shown in FIG. 1.

FIG. 17 is an exploded perspective view of the drive unit shown in FIG.16.

FIG. 18 is a perspective view of the drive unit shown in FIG. 16 withthe cover removed.

FIG. 19 is a perspective view of the drive unit shown in FIG. 18 withthe COS coupler removed.

FIG. 20 is a partially exploded perspective view of the drive unit shownin FIG. 19 with the mounting bracket removed.

FIG. 21 is a front plan view of a motor coupler according to the presentinvention for use with the drive unit shown in FIG. 16.

FIG. 22 is an elevated perspective view of a COS coupler operativelyconnected to the motor coupler shown in FIG. 21.

FIG. 23 is a perspective view of a rotatable motor cover according tothe present invention for use with the drive unit shown in FIG. 16.

FIG. 24 is a partial view of a cross-section of the drive unit shown inFIG. 16.

FIG. 25 is perspective view of an inner surface of a PCB board accordingto the present invention for use with the drive unit shown in FIG. 16.

FIG. 26 is a functional block diagram of a door closer assemblyaccording to an exemplary embodiment of the present invention;

FIG. 27 is a diagram of door opening and closing regions according to anexemplary embodiment of the present invention;

FIG. 28 is a diagram of a table translating a door position angle topinion position angle according to an exemplary embodiment of thepresent invention;

FIG. 29 is a diagram of selectors used to set desired door opening andclosing operation parameters according to an exemplary embodiment of thepresent invention;

FIG. 30 is an exemplary diagram a control unit according an exemplaryembodiment of the present invention;

FIG. 31 is an exemplary diagram an exploded view of a control unitaccording an exemplary embodiment of the present invention;

FIG. 32 is a diagram of a detailed view of a star gear and componentsthat interact with the star gear according to an exemplary embodiment ofthe present invention;

FIGS. 33A and 33B are diagrams of a top view of a star gear and a pullarm in a home position and an associated position of a trigger,respectively according to an exemplary embodiment of the presentinvention;

FIGS. 34A and 34B are diagrams of a top view of a star gear and a pullarm in a maximum rotation position and an associated position of atrigger, respectively according to an exemplary embodiment of thepresent invention;

FIGS. 35-37 are diagrams of a trigger and gear train assembly accordingto an exemplary embodiment of the present invention;

FIG. 38 is a diagram of the assembly of FIG. 37 from a side viewperspective according to an exemplary embodiment of the presentinvention;

FIGS. 39 and 40 show diagrams of a gear train according to an exemplaryembodiment of the present invention;

FIG. 41 is a gear train in a door closer according to an exemplaryembodiment of the present invention;

FIG. 42 is a block diagram of a control unit printed circuit board forcontrolling a valve of a door closer according to an exemplaryembodiment of the present invention;

FIG. 43 is a diagram of a circuit for conserving power in a door closerassembly according to an exemplary embodiment of the present invention;

FIG. 44 is a flowchart of a process for self-powered operation of a doorcloser according to an exemplary embodiment of the present invention;

FIG. 45 is a flowchart of a process for self-powered operation of a doorcloser according to another exemplary embodiment of the presentinvention;

FIG. 46 is a flowchart of a process for processing a door movementaccording to an exemplary embodiment of the present invention;

FIG. 47 is a flowchart of a process for processing a door movementaccording to another exemplary embodiment of the present invention;

FIG. 48 is a flowchart of a process for processing a door movementaccording to a still further exemplary embodiment of the presentinvention.

DESCRIPTION

Certain terminology is used herein for convenience only and is not to betaken as a limitation on the invention. For example, words such as“upper,” “lower,” “left,” “right,” “horizontal,” “vertical,” “upward,”and “downward” merely describe the configuration shown in the FIGs.Indeed, the components of the door closer may be oriented in anydirection and the terminology, therefore, should be understood asencompassing such variations unless specified otherwise.

As used herein, the term “open position” for a door means a doorposition other than a closed position, including any position betweenthe closed position and a fully open position as limited only bystructure around the door frame, which can be up to 180° from the closedposition.

Referring now to the drawings, wherein like reference numerals designatecorresponding or similar elements throughout the several views, a doorcloser assembly according to the present invention is shown andgenerally designated at 50. Referring to FIG. 1, the door closerassembly 50 is mounted to a door 52 in a door frame 54. The door 52 ismovable relative to the frame 54 between a closed position and an openposition. For the purpose of this description, only the upper portion ofthe door 52 and the door frame 54 are shown. The door 52 is of aconventional type and is pivotally mounted to the frame 54 for movementfrom the closed position, as shown in FIG. 1, to an open position foropening and closing an opening through a building wall to allow a userto travel from one side of the wall to the other side of the wall.

As shown in FIGS. 1 and 2, the door closer assembly 50 according to thepresent invention comprises a door closer 60, including a linkageassembly 61 for operably coupling the door closer assembly 50 to thedoor frame 54, a drive unit 62, and a control unit 64. As seen in FIG.2, ends of a rotating pinion 66 extend from the top and bottom of thedoor closer 60 for driving the linkage assembly 61 to control theposition of the door 52. FIG. 1 shows a linkage assembly 61 for a pushside mounting of the door closer assembly 50 to the door 52, comprisinga first rigid connecting arm link 68 and a second rigid connecting armlink 70. The first connecting arm link 68 is fixed at one end forrotation with the upper end of the pinion 66 (FIG. 1) and at the otherend is pivotally connected to an end of the second connecting arm link70. The other end of the second connecting arm link 70 is pivotallyjoined to a mounting bracket 72 fixed to the door frame 54. A linkageassembly 61 for a pull side mounting of the door closer assembly 50 tothe door 52 is also suitable. Both push side and pull side mounting ofthe linkage assemblies are well known in the art. Further, it should beunderstood that the linkage assembly 61 for use in the present inventionmay be any arrangement capable of linking the door closer 60 to the door52 in such a manner that the door closer assembly 50 affects movement ofthe door 52. Thus, numerous alternative forms of the linkage assembly 61may be employed.

The door closer assembly 50 is securely mounted to the upper edge of thedoor 52 using mounting bolts (not shown), or other fasteners. The doorcloser assembly 50 extends generally horizontally with respect to thedoor 52. The drive unit 62 and control unit 64 are fixed to the doorcloser 60. A cover (not shown) attaches to the door closer assembly 50.The cover serves to surround and enclose the components of the doorcloser assembly 50 to reduce dirt and dust contamination, and to providea more aesthetically pleasing appearance. It is understood that althoughthe door closer assembly 50 is shown mounted directly to the door 52,the door closer assembly 50 could be mounted to the door frame 54 or tothe wall adjacent the door frame 54 or concealed within the wall or doorframe 54. Concealed door closer assemblies are well known in the art ofautomatic door closer assemblies.

The door closer 60 is provided for returning the door 52 to the closedposition by providing a closing force on the door 52 when the door is inan open position. The door closer 60 includes an internal return springmechanism such that, upon rotation of the pinion 66 during door 52opening, the spring mechanism will be compressed for storing energy. Asa result, the door closer 60 will apply on the linkage assembly 61 amoment force which is sufficient for moving the door 52 in a closingdirection. The stored energy of the spring mechanism is thus released asthe pinion 66 rotates for closing the door 52. The closingcharacteristics of the door 52 can be controlled by a combination of theloading of the return spring mechanism and the controlled passage offluid through fluid passages between variable volume compartments in thedoor closer housing, as described more fully below.

FIGS. 3-7 depict an embodiment of the door closer 60 according to thepresent invention. The door closer 60 comprises a housing 65 foraccommodating the pinion 66, a piston 74, a spring assembly 80, and avalve assembly 100. The housing 65 defines an internal chamber which isopen at both ends.

The pinion 66 is an elongated shaft having a central gear tooth portion76 bounded by intermediate cylindrical shaft portions 77. The pinion 66is rotatably mounted in the housing 65 such that the pinion 66 extendsnormal to the longitudinal axis of the housing 65. The intermediatecylindrical shaft portions 77 of the pinion 66 are rotatably supportedin bearings 78 each held between an inner washer 82 and an outerretaining ring 83 disposed within opposed annular bosses 85 formed onthe top surface and the bottom surface of the housing 65. The outer endsof the shaft of the pinion 66 extend through the openings in the bosses85 and outwardly of the housing 65. The ends of the pinion 66 are sealedby rubber u-cup seals 86 which fit over the ends of the pinion 66 andprevent leakage of a hydraulic working fluid from the chamber of thehousing 65. The periphery of the bosses 85 are externally threaded forreceiving internally threaded pinion seal caps 88.

The spool-shaped piston 74 is slidably disposed within the chamber ofthe housing 65 for reciprocal movement relative to the housing 65. Theannular ends of the piston 74 seal against the inside wall of thehousing 65 to establish a fluid tight relation between the ends of thepiston 74 and the housing 65. In this arrangement, as shown in the FIGS.5-7, the piston 74 divides the chamber in the housing 65 into a firstvariable volume chamber 91 between one end of the piston 74 and thevalve assembly 100 and a second variable volume chamber 95 between theother end of the piston 74 and the spring assembly 80. The centralportion of the piston 74 is open and defines opposed rack teeth 75. Thepinion 66 is received in the open central portion of the piston 74 suchthat the gear teeth 76 on the pinion 66 engage the rack teeth 75 in thepiston 74. It is thus understood that rotation of the pinion 66 willcause linear movement of the piston 74 in a conventional manner known inthe art.

The spring assembly 80 comprises two compression springs 89, one nestedinside the other and supported between the piston 74 and an end plugassembly 90. The end plug assembly includes an end plug 92, an adjustingscrew 94, and a retaining ring 96. The end plug 92 is an externallythreaded disc sealingly secured in the threaded opening in the end ofthe housing 65. The end plug 92 is sealed to the wall of the housing 65with the retaining ring 96 disposed in a circumferential groove on theperiphery of the end plug 92. The end plug 92 thus effectively seals theend of the housing 65 against leakage of fluid. The adjusting nut 94 isheld in the housing 65 between the springs 89 and the end plug 92. Thesprings 89 urge the piston 74 towards the left end of the housing 65, asseen in FIGS. 5-7. The adjusting nut 94 is accessible by tool from theend of the housing 65, and rotating the adjusting nut 94 sets theinitial compressed length of the springs 89.

A fluid medium, such as hydraulic oil, is provided in the chamber in thehousing 65 to cooperate with the piston 74. As seen in FIG. 6, thehousing 65 is provided with a passage 110 though which fluid istransferred during reciprocal movement of the piston 74 in the chamberfor regulating movement of the door 52. The fluid passage 110 runslongitudinally between a radial passage 112 opening into the end of thehousing 65 adjacent the valve assembly 100 to a radial passage 114opening into the chamber adjacent the spring assembly 80. The passage110 thus serves as a conduit for fluid to pass between the firstvariable volume chamber 91 on one side of the piston 74 and the secondvariable volume chamber 95 on the other side of the piston 74.

The valve assembly 100 is sealingly secured in the opening in the end ofthe housing 65 adjacent the piston 74. Referring to FIGS. 8-15, thevalve assembly 100 comprises a valve housing 120, a valve sleeve 122, avalve shaft 124 and a spool plate 126. The valve housing 120 is acylindrical member including a relatively short cylindrical projection128 at an outer end. The valve housing 120 defines a central axialopening 121 therethrough. The outer end of the valve housing 120 definesa portion of the opening 121 having a smaller diameter than theremainder of the opening thereby forming a shoulder 130 (FIGS. 11, 12and 15) in the axial opening 121 adjacent the outer end of the valvehousing 120. The inner end of the housing 120 has six spaced axial bores132, 134, 136, 138 in the inner surface of the housing. Three equallyspaced bores 132 are threaded screw holes and three are fluid passages134, 136, 138. Spaced circumferential grooves 140 are provided in theperiphery of the valve housing 120 for receiving o-rings 142. Thegrooves 140 define an intermediate circumferential surface into whichradial passages 144, 146, 148, 150, 151 (FIGS. 13 and 14). Four of theradial passages 144, 146, 148, 150 are drilled through to the centralaxial opening 121.

The cylindrical valve sleeve 122 fits into the opening 121 in the valvehousing 120. The valve sleeve 122 defines a central axial opening 123therethrough. The valve sleeve 122 has four circumferentially spacedradial openings 152 opening into the central axial opening 123. Thevalve sleeve 122 has a smaller axial passage 162 therethrough (FIG. 15).A small radial bore 164 in the periphery of the valve sleeve 122connects to the axial passage 162. The valve sleeve 122 fits into thevalve housing 120 such that each of the radial openings 152 is alignedwith one of the radial openings 144, 146, 148, 150 in the valve housing120. As best seen in FIG. 11, one corresponding set of the openings 148,152 is sized to receive a hollow pin 160 for locking the valve sleeve122 to the valve housing 120.

The cylindrical valve shaft 124 is journaled inside the valve sleeve122. The outer end of the valve shaft 124 carries a cut off shaft 170with a square end. Opposed partial circumferential grooves 172, 173 areprovided intermediate the ends of the valve shaft 124. The valve shaft124 is configured such that the grooves 172, 173 are at the samerelative axial position as the radial openings 152 in the valve sleeve122.

The spool plate 126 is attached to the inner surface of the valvehousing 120 for holding the valve sleeve 122 in place. The spool plate126 has a depression 177 which corresponds to the axial passage 162 inthe valve sleeve 122 for fluid transfer during high pressure situations(FIG. 15).

The valve assembly 100 fits into the end of the housing 65 (FIGS. 3,5-7). Each of the outer surface of the valve housing 120 and the end ofthe housing 65 has a depression 176 for receiving an anti-rotation tab178. An externally threaded disc 180 and o-ring 181 is secured in thethreaded opening in the end of the housing 65. The cut off shaft 170 onthe valve shaft 124 extends through a central hole in the disc 180 andis held in place by the disc 180. As seen in FIGS. 5-7, acircumferential groove 182 is provided in the housing 65. With the valveassembly 100 in place, the groove 182 is disposed between the o-rings142 for forming a fluid path around the periphery of the valve housing120.

When the door 52 is in the fully closed position, the components of thedoor closer 60 according to the present invention are as shown in FIG.5. As the door 52 is opened, the door rotates the pinion 66 and therebyadvances the piston 74 linearly to the right as seen in FIGS. 6 and 7.Movement of the piston 74, in turn, compresses the springs 89 betweenthe piston 74 and the end plug 92. It is understood that the door closerassembly 50 can be used on a left hand door or a right hand door and,therefore, the door could be opened in a either a clockwise or acounterclockwise direction, as viewed in FIG. 1.

As the piston 74 moves toward the right end of the chamber in thehousing 65, the fluid surrounding the springs 89 is forced through theradial passage 114 and into the longitudinal fluid passage 110. Thefluid passes through the radial passage 112 at the end of the housing 65adjacent the valve assembly 100 and into the groove 182 in the housing65. Fluid thus surrounds the central portion of the valve housing 120between the o-rings 142 such that the opposed radial bores 144, 148 arein fluid communication with the main fluid passage 110 through thehousing 65 (FIG. 6). The fluid flows into the long radial passages 144,148 in the valve housing 120 and the through the openings 152 in thevalve sleeve 122 toward the valve shaft 124. If the valve shaft 124 isin a closed position (FIG. 13), the fluid cannot advance. If the valveshaft 124 is rotated to the open position shown in FIG. 14, the fluidcan flow to the radial passages 146, 150 and to the axial passages 134,136 which open into the first variable volume chamber 91. The degree ofrotation of the valve shaft 124 relative to the valve sleeve 122regulates the rate of fluid flow past the valve shaft 124. When the door52 reaches a fully open position, the piston 74 is in the position shownin FIG. 7 and the springs 89 are compressed.

Movement of the door 52 from an open position to the closed position iseffected by expansion of the springs 89 acting to move the piston 74 tothe left as seen in FIGS. 5-7. The advancing piston 74 causes the pinion66 to rotate for moving the door 52 toward the closed position. Fluid isforced out of the first variable volume chamber 91 in the housing 65,through the valve assembly 100, and the housing passages 110, 112, 114and into the second variable volume chamber 95 around the springs 89.Specifically, the fluid initially flows into the axial passages 134, 136and then to the corresponding radial passages 146, 150 to the valveshaft 124. If the valve is closed, the fluid cannot advance. If thevalve shaft is rotated to the open position shown in FIG. 14, the fluidexits via the grooves 172, 173 of the valve shaft 124 and into theradial passages 144, 148 in the valve housing 120 toward the housingpassages 110, 112, 114. Fluid again surrounds the central portion of thevalve housing 120 between the o-rings 142 and exits through housingpassage 112. The degree of rotation of the valve shaft 124 relative tothe valve sleeve 122 will affect the rate of fluid flow past the valveshaft 124 and, thus, the speed of movement of the closing door 52. Whenthe door 52 reaches the closed position, the components of the doorcloser 60 are again as shown in FIG. 5.

As seen in FIG. 15, a radial vent passage 184 is provided in the valvehousing and is arranged in fluid communication with the radial bore 164in the valve sleeve 122 which communicates with the axial vent passage162. The openings to vent passages 138, 184 in the valve housing 120 arecounter-bored for receiving check balls 185, 186. The diameter of theballs 185, 186 are larger than a smaller outer diameter portion of thepassages 138, 184 for allowing only one-way fluid flow. This arrangementof fluid passages serves as a vent relief in high pressure situations.Specifically, during door opening, if the pressure in the fluid flowpath becomes excessive, the pressure may force the ball 186 into thelarger diameter portion of the passage 138 so as to open the passageallowing fluid flow through the passage 138.

It is understood that fluid pressure forces the other ball 185 onto thesmaller outer diameter of the corresponding passage 184. Fluidsurrounding the valve shaft 124 can exit outwardly via the radialpassage 164 in the valve sleeve 122 and the radial passage 184 in thevalve housing 120 and out the axial vent passage 138 in the valvehousing 120 and in the first variable volume chamber 91 via the hole 127in spool plate 126. During door closing, if the pressure in the fluidflow path becomes excessive, the pressure may force the ball 185 intothe larger diameter portion of the passage 184 so as to open the passageallowing fluid flow through the passage 184. It is understood that fluidpressure forces the other ball 186 onto the smaller outer diameter ofthe corresponding passage 138. Fluid surrounding the valve shaft 124will thus exit outwardly via the radial passage 164 in the valve sleeve122 and will continue outwardly through the radial vent passage 184 tothe groove 182 in the housing 65 and out of the area via the housingpassages 110, 112, 114.

According to an embodiment of the present invention, the position of thevalve shaft 124 may be dynamically changed during door movement forcontrolling the flow of fluid past the valve shaft 124 and through thepassages. Thus, as the door opens and closes, the valve position can bechanged in order to provide varying levels of hydraulic resistance as afunction of door angle. Fluid flow is controlled by powered rotationalmovement of the valve shaft 124, referred to herein as the “cut-offshaft (COS)” 124. In this regard, many conventional valves have a screw,referred to herein as the “cut-off screw,” that is used to control thevalve's “angular position.” That is, as the cut-off screw is rotated,the valve's angular position is changed. The valve's “angular position”refers to the state of the valve setting that controls the valve's flowrate. For example, for valves that employ a cut-off screw to controlflow rate, the valve's “angular position” refers to the position of thecut-off screw. In this regard, turning the cut-off screw in onedirection increases the valve's angular position such that valve allowsa higher flow rate through the valve. Turning the cut-off screw in theopposite direction decreases the valve's angular position such that theflow through the value is more restricted (i.e., the flow rate is less).In one embodiment, the valve assembly 100 is conventional having acut-off screw 170, and the COS 124 is coupled to the valve's cut-offscrew 170 that controls flow rate. Thus, rotation of the COS 124 changesthe angular position of the valve shaft 124 and, therefore, affects thefluid flow rate.

The drive unit 62 is coupled to the COS 124 and rotates the COS 124 asappropriate to control the angular position of the valve shaft 124 in adesired manner, as will be described in more detail below. Referring toFIGS. 16 and 17, the drive unit 62 comprises a COS coupler 190, a motorcoupler 192, a servo motor 194, a mounting bracket 196, a coverincluding a fixed cap 198 and a rotating cap 200, and a PCB board 202.As shown in FIGS. 17 and 18, the COS coupler 190 includes a disc 245with a hollow tab extension 247 positioned at a center of the disc 245.The tab 247 defines a hole 249 for receiving the cut-off screw 170. Thecenter of the hole 249 is aligned with the center of the disc 245. Theinner wall of the tab 247 is dimensioned such that the cut-off screw 170fits snugly into the tab 247 for fixed rotation of the cut-off screw 170and the COS coupler 190 (FIGS. 5-7).

Referring to FIGS. 20 and 21, the motor coupler 192 is also a dischaving a hollow tab extension 275 positioned at a center of the motorcoupler 192. The tab 275 defines an opening 278 for receiving a motorshaft 276, which is rotated by the motor 194. The inner wall of the tab275 is dimensioned such that the motor shaft 276 fits snugly in the tab275 for fixed rotation of the shaft 276 and the motor coupler 192. Themotor coupler 192 has another hollow tab extension 279 into which anaxially extending pin 255 is inserted. The inner wall of the tab 279 isdimensioned such that the pin 255 fits snugly in the tab 279, andfrictional forces generally keep the pin 255 stationary with respect tothe motor coupler 192. Therefore, any rotation of the motor coupler 192moves the pin 255 about the center of the motor shaft 276. The motorcoupler 192 has yet another hollow tab extension 283 into which a magnet286 is inserted. For example, in one exemplary embodiment, the magnet286 is glued to the motor coupler 192, but other techniques of attachingthe magnet 286 to the motor coupler 192 are possible in otherembodiments. As the motor coupler 192 rotates, the magnet 286 rotatesabout the center of the motor shaft 276.

Referring to FIGS. 18 and 22, the COS coupler disc 245 has a slot 252which receives the pin 255 on the motor coupler 192. The slot 252 isdimensioned such that its width (in a direction perpendicular to ther-direction) is slightly larger than the diameter of the pin 255 so thatfrictional forces do not prevent the COS coupler 190 from movingrelative to the pin 255 in the y-direction, which is parallel to thecenterline of the pin 255. Therefore, if the COS coupler 190 receivesany mechanical forces in the y-direction, such as forces from a userkicking or slamming the door 52 or from pressure of the fluid flowing inthe valve assembly 100, the COS coupler 190 is allowed to move in they-direction relative to the pin 255 thereby preventing such forces frompassing through the pin 255 to other components, such as the motor 194,coupled to the pin 255. Such a feature can help prevent damage to suchother components and, in particular, the motor 194. In addition, asshown by FIG. 22, the radial length of the slot 252 in the r-directionis significantly greater than the diameter of the pin 255 such that itis unnecessary for the alignment between the couplers 190, 192 to beprecise. Indeed, any slight misalignment of the couplers 190, 192 simplychanges the position of the pin 255 along a radius of the COS coupler190 without creating stress between the pin 255 and the COS coupler 190.That is, slight misalignments between the COS coupler 190 and the motorcoupler 192 changes the location of the pin 255 in the r-direction.However, since the pin 255 can freely move to at least an extent in ther-direction relative to the COS coupler 190, such misalignments do notcreate stress in either of the couplers 190, 192.

In one exemplary embodiment, the width (perpendicular to ther-direction) of the slot 252 is about equal to or just slightly largerthan the width of the pin 255. Thus, the width of the slot 252 is smallenough so that any rotation of the motor coupler 192 causes acorresponding rotation of the COS coupler 190 but is large enough sothat significant friction or other mechanical forces are not induced bymovement of the COS coupler 190 in the y-direction. Allowing the COScoupler 190 to move relative to the motor coupler 192 in the y-directionnot only prevents mechanical forces from transferring from the COScoupler 190 to the motor coupler 192 but also obviates the need toprecisely set the separation distance between the couplers 190, 192.

The couplers 190, 192 may be composed of plastic, which is typically alow cost material. Note that the shapes of the coupler components, aswell as the shapes of devices coupled to such components, can bechanged, if desired. For example, the cross-sectional shape of thecut-off screw 170 may be circular; however, other shapes are possible.For example, the cross-sectional shape of the cut-off screw 170 could bea square or rectangle. In such an example, the shape of the hole 249 inthe hollow tab extension 247 on the COS coupler 190 may be a square orrectangle to correspond to the shape of the cut-off screw 170. Inaddition, the cross-sectional shape of the disc 245 is shown to begenerally circular, but other shapes, such as a square or rectangle arepossible. Similarly, the motor coupler 192 and the pin 255 may haveshapes other than the ones shown explicitly in the figures.

In the embodiments described above, the pin 255 is described as beingfixedly attached to the motor coupler 192 but not the COS coupler 190.In other embodiments, other configurations are possible. For example, itis possible for a pin 255 to be fixedly coupled to a COS coupler andmovable relative to a motor coupler.

In addition, it should be further noted that it is unnecessary for thecouplers 190, 192 to rotate over a full 360 degree range duringoperation. In one exemplary embodiment, about a thirty-five degree rangeof movement is sufficient for providing a full range of angularpositions for the valve shaft 124. In this regard, assuming that thevalve shaft 124 is in a fully closed position such that the valve shaft124 allows no fluid flow, then rotating the integral cut-off screw 170about 35 degrees transitions the valve shaft 124 from the fully closedposition to the fully open position (i.e., the valve's flow rate is at amaximum for a given pressure). In such an example, there is no reasonfor the cut-off screw 170 to be rotated outside of such a 35 degreerange. However, the foregoing 35 degree range is provided herein asmerely an example of the possible range of angular movements for thevalve shaft 124, and other ranges are possible in other embodiments.

The motor 194 (FIG. 20) is an electric reversible motor with the motordrive shaft 276, a portion of which extends from the housing of themotor 194. The motor 194 is reversible such that the rotation of themotor 194 in one direction will cause the drive shaft 276 to rotate inone direction and rotation of the motor 194 in the opposite directionwill cause the drive shaft 276 to rotate in the opposite direction. Suchmotors are widely commercially available and the construction andoperation of such motors are well known; therefore, the details of themotor 194 are not described in specific detail herein. A suitable motor194 for use in the door closer assembly 50 of the present invention is a3 volt motor providing a gear ratio of 109:1 and a rated torque of 1.3oz-in. The motor 194 operates under the direction and control of thecontrol unit 64, which is electrically coupled to the motor via anelectrical cable.

The motor 194 is secured to the mounting bracket 196 (FIG. 17) and thento the door closer housing 65 using threaded fasteners received in axialthreaded openings 67 in the corners of the end of the housing 65 (FIG.3). A sealing ring 208 is received in a corresponding recess in themounting bracket 196 and fits against the door closer housing 65. Thesealing ring 208 helps to keep any water from seeping between the driveunit 62 and the door closer 60 from reaching the various electricalcomponents of the drive unit.

One advantage of the exemplary design of the couplers 190, 192 is thatit facilitates assembly. In this regard, as described above, precisetolerances between the cut-off screw 170 and the motor shaft 276, aswell as between couplers 190, 192, is unnecessary. Such a feature notonly facilitates assembly but also promotes interchangeability. Forexample, the couplers 190, 192 may be used to reliably interface a motor194 and door closer 60 of different vendors. Moreover, to interface themotor 194 with the door closer 60, a user simply attaches the COScoupler 190 to the COS shaft 124 and positions the couplers 190, 192such that the pin 255 is able to pass through the slot 252 as the motor194 is mounted on the door closer 60. The motor 194 can be secured tothe mounting bracket 196 via screws 288 or other attachment mechanisms.As described above, there is no need to precisely align the couplers190, 192 as long as the couplers 190, 192 are appropriately positionedsuch that the pin 255 passes through the slot 252.

In this regard, slight misalignments of the couplers 190, 192 do notcreate significant stresses between the couplers 190, 192. For example,assume that the couplers 190, 192 are slightly misaligned such that thecenterline of the COS 124 does not precisely coincide with thecenterline of the motor shaft 276. That is, the center of rotation ofthe COS coupler 190 is not precisely aligned with the center of rotationof the motor coupler 192. In such an example, the pin 255 moves radiallyrelative to the COS coupler 190 as the couplers 190, 192 rotate. Inother words, the pin 255 moves toward and/or away from the center ofrotation of the COS coupler 190 as the couplers 190, 192 rotate. If thepin 255 is not movable along a radius of the COS coupler 190 when thecouplers 190, 192 are misaligned, then the rotation of the couplers 190,192 would induce stress in the couplers 190, 192 and pin 255. However,since the pin 255 is radially movable relative to the COS coupler 190due to the dimensions of the slot 252, such stresses do not occur.

In addition, as described above, the COS coupler 190 is movable in they-direction (i.e., toward and away from the motor coupler 192) withoutcreating stresses in the couplers 190, 192 or transferring significantforces from the COS coupler 190 to the motor coupler 192. In thisregard, the pin 255 is not fixedly attached to the COS coupler 190, andthe length of the slot 252 in the r-direction (i.e., along a radius ofthe COS coupler 190) is sufficiently large so that the COS coupler 190can slide along the pin 255 (or otherwise move relative to the pin 255)without transferring forces through the pin 255 to the motor coupler192.

As shown by FIG. 16, the fixed cover 198 is coupled to the mountingbracket 196 with screws. As shown by FIG. 24, the fixed cover 198 iscoupled to the rotatable cover 200, which can be rotated relative to thefixed cover 198. Referring to FIG. 23, the rotatable cover 200 has a lip681 that extends around a perimeter of the cover 200. The cover 200 hasa plurality of notches 683 along such perimeter, but such notches 683are unnecessary in other embodiments. The interior of the fixed cover198 forms a channel 686 (FIG. 24) into which the lip 681 fits andthrough which the lip 681 slides. A tab 688 extends from the lip 681 andlimits the movement of the cover 200 relative to the fixed cover 198. Inthis regard, the fixed cover 198 has a pair of stops (not shown). Thecover 200 is rotatable with the tab 688 between the stops. As the cover200 is rotated in one direction, the tab 688 eventually contacts one ofthe stops preventing further movement of the cover 200 in suchdirection. As the cover 200 is rotated in the opposite direction, thetab 688 eventually contacts the other stop preventing further movementof the cover 200 in such direction. In one exemplary embodiment, thecover 200 is rotatable up to 180 degrees (i.e., half of fullrevolution). Limiting the movement of the cover 200 helps to prevententanglement of a motor cable (not shown) that is within the cover 200.

The rotatable cover 200 has a receptacle 215 for receiving electricalwires, such as the electrical cable 277 from the control unit 64. Themotor cable (not shown) has a connector that electrically connects themotor cable to the cable 277 from the control unit 64. Thus, one end ofthe motor cable is connected to the cable 277 from the control unit 64,and the other end is connected to the motor 194 thereby electricallyconnecting the motor 194 to the control unit 64. Since the cover 200 isrotatable, it is possible to position the control unit 64 at variouslocations, such as either on top of or below the hydraulic door closer60, and to then rotate the cover 200 until the receptacle 215 isoriented in a manner conducive to receiving the cable 277. In addition,the cover 200 may be rotated such that the receptacle 215 is generallyfaced downward in order to help keep rainwater from falling into thereceptacle 215 and reaching electrical components housed by the covers198, 200. In one exemplary embodiment, the covers 198, 200 are bothcomposed of plastic, but other materials for the covers are possible inother embodiments.

Referring to FIGS. 19 and 20, a PCB board 202 is positioned between themotor coupler 192 and the COS coupler 190. In one exemplary embodiment,the PCB board 202 is attached to the mounting bracket 196 via, forexample, screws 203 (FIG. 17), but other techniques for mounting the PCBboard 202 on the mounting bracket 196 or other component are possible inother embodiments. As shown by FIG. 25, a magnetic sensor 299 is mountedon an inner surface 298 of the PCB board 202. The magnetic sensor 299 isconfigured to detect a strength of the magnetic field generated by themagnet 286 on the motor coupler 192. Such a detection is indicative ofthe angular position of the valve shaft 124 of the door closer 60. Inthis regard, to change such angular position, the motor 194 rotates themotor shaft 276 causing the motor coupler 192 to rotate. Such rotationis translated to the COS coupler 190 through the pin 255. In thisregard, rotation of the motor coupler 192 moves the pin 255 about themotor shaft 276. When moving, the pin 255 presses against and moves theCOS coupler 190. In particular, the pin 255 rotates the COS coupler 190and, therefore, the cut-off screw 170 that is inserted into the hollowtab extension 247. The rotation of the cut-off screw 170 changes theangular position of the valve shaft 124. Since rotation of the motorcoupler 192 ultimately changes the angular position of the valve shaft124, the position of the magnet 286 relative to the sensor 299 on thePCB board 202, which is stationary, indicates the angular position ofthe valve shaft 124.

The sensor 299 is configured to transmit a signal having a voltage thatis a function of the magnetic field strength sensed by the sensor 299.In one exemplary embodiment, the sensor 299 is a ratiometric sensor suchthat a ratio (R) of the sensor's input voltage to the sensor's outputvoltage is indicative of the angular position of the valve shaft 124. Inthis regard, each discrete angular position of the valve shaft 124 isassociated with a specific voltage ratio (R), which is equal to theinput voltage of the sensor 299 divided by the output voltage of thesensor 299. For example, assume that to open the valve shaft 124 more sothat flow rate increases, the motor coupler 192 is rotated such that themagnet 286 is moved closer to the sensor 299 thereby increasing themagnetic field strength sensed by the sensor 299. In such an example, Rincreases the more that the valve shaft 124 is opened. Further, Rdecreases when the motor coupler 192 is rotated such that the magnet 286is moved away from the sensor 299. Thus, R decreases as the valve shaft124 is closed in order to decrease flow rate.

In one exemplary embodiment, control logic 280 stores data 301, referredto herein as “valve position data,” that maps various possible R valuesto their corresponding angular positions for the valve shaft 124. Thus,the control logic 280 can determine an R value from a reading of thesensor 299 and use the stored data 301 to map the R value to the valve'sangular position at the time of the reading. In other words, based onthe reading from sensor 299 and the mappings stored in the valveposition data 301, the control logic 280 can determine the angularposition of the valve 69.

Note that the use of a ratiometric sensor can be desirable inembodiments for which power is supplied exclusively by a generator 294.In such an embodiment, conserving power can be an important designconsideration, and it may be desirable to allow the input voltage of thesensor 299 to fluctuate depending on power demands and availability.Using a voltage ratio to sense valve position allows the input voltageto fluctuate without impairing the integrity of the sensor readings. Inother embodiments, other types of magnetic sensors may be used to sensethe magnetic field generated by the magnet 286.

In one exemplary embodiment, the sensor 299 is coupled to the controlunit 64 via three wires of the cable 277. One wire carries an inputvoltage for the sensor 299. Another wire carries an output voltage forthe sensor 299, and the third wires carries an enable signal. In thisregard, the sensor 299 is configured to draw current from the controllogic 280 only when receiving an enable signal from the logic 280. Thus,if the sensor 299 is not receiving an enable signal via the third wire,the sensor 299 is not usurping any electrical power. Moreover, when thecontrol logic 280 desires to determine the current position of the valveshaft 124, the control logic 280 first transmits an enable signal to thesensor 299, waits a predetermined amount of time (e.g., a fewmicroseconds) to ensure that sensor 299 is enabled and providing areliable reading, reads a sample from the sensor 299, and then disablesthe sensor 299 thereby preventing the sensor 299 from drawing furthercurrent. Accordingly, for each reading, the sensor 299 draws currentonly for a short amount of time thereby helping to conserve electricalpower.

In one exemplary embodiment, readings from the sensor 299 are used toassist in the control of the motor 194. In such an embodiment, the motor194 is a servomotor, and the control logic 280 instructs the motor 194when and to what extent to rotate the motor shaft 276 (therebyultimately rotating the cut-off screw 170 by a corresponding amount) bytransmitting pulse width modulation (PWM) signals to the motor 194. Inthis regard, pulse width modulation is a known technique for controllingservomotors and other devices by modulating the duty cycle of controlsignals. Such techniques can be used to control the motor 194 such thatthe motor 194 drives the shaft 276 by an appropriate amount in order toprecisely rotate the shaft 276 by a desired angle.

In controlling the door closer 60, the control logic 280 may determinethat it is desirable to set the angular position of the valve shaft 124to a desired setting. For example, the control logic 280 may determinethat the angle of the door 52 has reached a point at which the forcegenerated by the closer 60 is to be changed by adjusting the angularposition of the valve shaft 124. If the current angular position of thevalve shaft 124 is unknown, the control logic 280 initially determinessuch angular position by taking a reading of the sensor 299. In thisregard, the control logic 280 enables the sensor 299, waits apredetermined amount of time to ensure that the sensor 299 is enabledand is providing a reliable value, and then determines the angularposition of the valve shaft 124 based on the sensor 299. In oneexemplary embodiment in which the sensor 299 is ratiometric, the controllogic 280 determines the ratio, R, of the sensor's input and outputvoltages and maps this ratio to a value indicative of the valve'scurrent angular position via the valve position data 301.

Based on the valve's current angular position, the control logic 280determines to what extent the cut-off screw 170 is to be rotated inorder to transition the valve shaft 124 to the desired angular position.For example, the control logic 280 can subtract the desired angularposition from the current angular position to determine the degree ofangular rotation that is required to transition the valve shaft 124 toits desired angular position. The control logic 280 then transmits a PWMsignal to the motor 194 to cause the motor to rotate the shaft 276 by asufficient amount in order transition the valve shaft 124 to its desiredangular position. In response, the motor 194 rotates the shaft 276thereby rotating the motor coupler 192. Since the pin 255 passes throughthe COS coupler 190, the COS coupler 190 rotates in unison with themotor coupler 192 thereby rotating the cut-off screw 170. Accordingly,the motor 194 effectively drives the cut-off screw 170 such that thevalve shaft 124 is transitioned to its desired angular position. Oncethe valve shaft 124 is transitioned to its desired angular position, thecontrol logic 280, if desired, can take another reading of the sensor299, according to the techniques described above, in order to ensurethat the valve shaft 124 has been appropriately set to its desiredangular position. If there has been any undershoot or overshoot of thesensor's angular position, the control logic 280 can transmit anotherPWM signal to the motor 194 in order to correct for the undershoot orovershoot.

FIG. 26 shows a functional block diagram of a door closer assemblyaccording to an exemplary embodiment of the present invention. Theexemplary door closer assembly 50 may include a door closer 60, acontrol unit 64, and a drive unit 62. The door closer 60 may include avalve 100 that regulates fluid in the door closer 60 causing the doorcloser 60 to control a speed of operation of the door 52. The drive unit62 may include a motor 194 that drives a cut-off shaft 124 to controlthe valve 100. The drive unit 62 may also include a valve sensor 299that monitors an angular position of the valve 100 based on a rotationof the valve shaft 124. The control unit 64 may include a processor 555,a regulator 545, an energy storage device 525, a generator 294, a gearassembly 996, control logic 997 and a door sensor 336. The processor 555may be connected to the drive unit 62 and the regulator 545. Theregulator 545 regulates an output voltage of the energy storage device525. The generator 294 receives power through the gear assembly 996based on movement of the door 52 and generates power used to charge theenergy storage device 525 power the processor 555, regulator 545, motor194 and any other electrical circuitry in the control unit 64. Thecontrol logic 997 and other components of the control unit 64 may resideon a printed circuit board (PCB). Further, although not shown, thecontrol unit 64 may have one or more storage devices that may storesoftware applications, data, control instructions, etc.

In embodiments according to the present invention, it is possible forthe control unit 64 to have a battery in addition or in lieu of thegenerator 294 in order to provide power to the electrical components ofthe door closer assembly 50. However, a battery, over time, must bereplaced. In one exemplary embodiment, the control unit 64 may bedesigned such that all of the electrical power used by the control unit64 is generated by the generator 294 so that use of a battery isunnecessary, or only used as a backup source of power. In otherembodiments according to the present invention, electrical power may bereceived from a battery or other types of power sources. Moreover,although not explicitly shown, the generator 294 and/or the energystorage device 525 may provide power to all appropriate components inthe control unit 64 as well as the motor 194 and appropriate componentsin the drive unit 62 and the door closer 60.

The door sensor 336 monitors an angular position of the door 52 based onmovement of the door 52. The processor 555 obtains data from the valvesensor 299 regarding the angular position of the valve and data from thedoor sensor 336 regarding the angular position of the door and uses bothdata to determine whether the position of the valve requires adjustment.The valve sensor 299 and the door sensor 336 may be in the form of Halleffect sensors where as the angular position of the valve shaft 124varies and the angular position of the door 52 varies a magnetic fielddetected by the valve sensor 299 and the door sensor 336, respectivelywill also vary. The processor 555 uses data from the magnetic fieldsdetected by the valve sensor 299 and the door sensor 336 to determine anassociated angular position of the valve and an associated angularposition of the door, respectively. To help illustrate embodimentsaccording to the present invention magnet sensors, e.g., Hall effectsensors, will be used for the valve sensor 299 and the door sensor 336,however, embodiments according to the present invention are not limitedto use of magnetic type sensors as any type of sensor that provides datauseable for determining an angular position of a valve shaft 124 and adoor 52 are within the scope of the present invention.

Moreover, according to embodiments of the present invention, one or moreswitches, knobs, or other types of selectors 999 (FIG. 29) may beaccessible external to the door closer assembly 50 allowing a user ofthe door closer assembly 50 to set desired values for a closer operationmode, a delayed action time, a backcheck position, a backcheckintensity, and a teach mode. The values set on the selectors may be usedby the processor 555 in determining adjustment of the valve 100. Theselectors 999 may be interconnected to a printed circuit board on thecontrol unit 64.

Further, control software in the control unit 64 may monitor a voltagelevel of the energy storage device, e.g., capacitor, and based oncomparisons against stored voltage references 998, change a mode ofoperation of the processor, shut down the processor, or permitadjustment of the valve 100.

FIG. 27 shows a diagram of door opening and closing regions according toan exemplary embodiment of the present invention. To help illustrateembodiments according the present invention, example values for variousdoor opening and closing parameters will be used, however, embodimentsof the present invention are not limited to the use of these exactvalues. Further, selectors may be used to set desired door opening andclosing operation parameters. In FIG. 27, seven dipswitches will be usedto help illustrate these selectors, however, any type of selectors suchas, for example, knobs, buttons, etc. may be used and be within thescope of the present invention. During a door opening cycle, the doorcloser 60 may begin control between a first door opening angle and asecond door opening angle, e.g., 60° and 85°, arresting motion by athird door opening angle, e.g. 90°. During the closing cycle, the doorcloser 60 must maintain control from a certain door opening angle, e.g.,115° to close. The closing speed of the door 52 may be maintained for aperiod of time, e.g. a 5 to 7 second closing time from 90° of dooropening. As the door 52 closes, there may be two regions of closingspeed. The first region may begin control at a certain door openingangle, e.g., 115°, from the door-closed position and continues to withina certain arc length, e.g., 12″, of the door-closed position. Thesemeasurements may be taken at a certain radius, e.g., 30″, from thedoor's pivot point. The second region may begin control at a certain arclength, e.g., 12″, from the door-closed position and continues to thedoor-closed position.

According to embodiments of the present invention, a sensor or encodermay be attached to a pinion connected to a door 52 to sense the doorposition and calculate its speed. This value may be used for monitoringspeed, position, and teaching of the mounting for the door closeroperation. A teach mode may be enabled when a Dipswitch 7 is turned on.This may serve as an override of existing settings that can be activatedto re-teach a Home and Fully Open position of the door 52 when a user(e.g., facilities/maintenance person who maintains the door closer)deems it necessary. An example operation of the teach mode may be: (1)Initiate Teach Mode (turn dipswitch on); (2) Open door to Fully Openposition and hold for a small period of time (e.g., 4 seconds); (3) Letdoor close to the Home position and then wait a small period of time(e.g., 4 seconds) after the door latches; and (4) End Teach Mode (turndipswitch off).

During operation, the door closer 60 may adjust a speed to a targetvalue (once each cycle) for each region of door travel by adjusting thevalve 100. If conditions arise where the closer operation is idle for anextended period of time the valve 100 may be adjusted to maintaincontrol of the door 52 based upon normal operation. The speed for eachregion may need to be measured and stored for future adjustment. Thevalue for each speed may need to be calculated from the average of thelast few (e.g., five) speed readings. This may be initially preset fromthe factory. The valve may be set for each target speed in the cycle.Moreover, the valve 100 may need to be adjusted once for each range andnot continuously “search” for the perfect speed. The only exception maybe due to gross speed error. Door closers 60 may be initially setup withcertain settings (e.g., for a standard 90° opening, parallel mountingconfiguration) when received by a user where the user may change theseinitial settings if desired.

As shown in FIG. 26, the door speed may be controlled through oil flowrestriction in the door closer 60 between fully Open (2) and Home (1)(both opening and closing). Backcheck is the opening speed controlbetween (BC) and (2). The exemplary dipswitch-setting scheme belowidentifies an exemplary target speed for backcheck.

TABLE 1 B Dipswitch Dipswitch Backcheck Deg/Sec 1 2 Soft On On MediumOff Off Hard On Off

If the door 52 is opened to a position between ((1)+70°)) and (2), thenDelay Action as set below may be applied. Delay action may hold the door52 (shut down the valve) for D seconds. The delay may only be used ifthe door 52 was opened to a position between ((1)+70°)) and (2) and thedipswitch is set for Delay Action.

The dipswitch-setting scheme below identifies the target delay times. IfD is defined as 0 Seconds, then there is no delay action.

TABLE 2 D Dipswitch Dipswitch Delay Action Seconds 3 4 None 0 On OnStandard 10 Off Off Long 20 On Off

On the closing cycle, closer speed control may be applied between (2)and (L) (after delay). On the closing cycle, latch speed control may beapplied between (L) and (1).

The dipswitch-setting scheme below identifies the target closer & latchspeeds.

TABLE 3 C L Dipswitch Dipswitch Closer Speed Deg/Sec Deg/Sec 5 6 Normal15 10 On On ADA 10 30 Off Off Security 20 10 On Off

FIG. 28 shows a diagram of a table translating a door 52 position angleto a pinion 66 position angle according to an exemplary embodiment ofthe present invention. The table shows door angles ranging from 0degrees to 180 degrees in 10 degree increments and their associatedpinion angle per a mounting type. The mounting types may include aregular mounting, a parallel mounting and a top jamb mounting. Values inthis table may be used to determine an angular position of the door 52.

FIG. 29 shows a diagram of selectors 999 used to set desired dooropening and closing operation parameters according to an exemplaryembodiment of the present invention.

FIGS. 30 and 31 show an exemplary diagram of a control unit 64 accordingan exemplary embodiment of the present invention. The components of thecontrol unit 64 may be housed in an enclosure 147, which can be mountedon a bottom of the door closer 60, or at another location, such as ontop of the door closer 60. The control unit 64 may include a printedcircuit board (PCB) 79. The components of the PCB 79 receive electricalpower from a generator 294 (described in more detail following). A stargear 102 receives an end of the pinion 66, which rotates the star gear102 when the door 52 is moving. The star gear 102 has a plurality ofteeth 105 formed along the outer edge of the gear 102. As the star gear102 rotates, the gear teeth 105 engage a force activator 108 causing theforce activator 108 to push a pull arm 111 in generally the x-directionso that the arm 111 pivots about a pivot point 214, as indicated in FIG.30. The x-direction is generally in a direction towards the end of thecontrol unit 64 with the ribbon cable 277. An end of the pull arm 111 iscoupled to a wire 221 (or a cord, a rod, etc.), which is also coupled toa movable trigger 125. When forced in the x-direction, the pull arm 111pulls the trigger 125 in the same direction.

The trigger 125 may be spring loaded by a spring 133. In this regard,the trigger's 125 movement in the x-direction elongates the spring 133.As the activator 108 is forcing the pull arm 111 in the x-direction, apoint is reached at which continued rotation by the star gear 102 causesthe tooth 105 in contact with the activator 108 to disengage theactivator 108. At this point, the spring 133 forces the trigger 125 in adirection opposite of the x-direction. As the star gear 102 continues torotate, another tooth 105 of the star gear 102 makes contact with theactivator 108 causing the force activator 108 to again push the pull arm111 in the x-direction causing the arm 111 to pivot about the pivotpoint 214 and to again pull the trigger 125 in the same x-direction, andthe process repeats as the star gear 102 turns responsive to movement ofthe door 52. When the door 52 is in motion and the trigger 125 is pulledin the x-direction and then in a direction opposite the x-direction, thetrigger's connection to a gear train 242 causes the rotation of at leastone gear in the gear train 242 that translates through the gear train242 to the generator 294. The generator 294 harnesses this energy andgenerates an electrical pulse for each movement of the trigger 125. Theelectrical pulses generated by the generator 294 may be used to powercomponents of the control unit 64 and other items in the door closerassembly 50 without the need for other types of power. Further detailswill be discussed following.

According to embodiments of the present invention, the trigger 125 movesresulting in the generator 294 generating power when the door 52 ismoving. When the door 52 is no longer moving, such as after the door 52fully closes, the generator 294 may stop generating power and variouselectrical components, such as components on the PCB 79, may beshut-off. Thus, the electrical power requirements of the door closerassembly 50 can be derived solely from movement of the door 52, ifdesired, with no need for an external power source.

Once a user begins opening the door 52, the door's movement istranslated into movement by the trigger 125 and, ultimately, electricalpower by the generator 294. When the generator 294 begins providingelectrical power, the electrical components are powered, and the closer60 is controlled in a desired manner until the door 52 closes orotherwise stops moving at which time various electrical components areagain shut-off. However, the techniques described above for generatingelectrical power are exemplary. Other techniques for providingelectrical power are within the scope of the present invention. Further,according to embodiments of the present invention, it may be unnecessaryor undesirable for electrical components to be shut-off when the door 52stops moving. The control unit 64 may also include selectors 999 suchas, for example, switches, dials, knobs, etc. for setting desired doorcloser operating parameters. These parameters may include, for example,a closer operation mode, a delayed action time, a backcheck position, abackcheck intensity, a teach mode, etc.

FIG. 32 shows a diagram of a detailed view of the star gear 102 andcomponents that interact with the star gear 102 according to anexemplary embodiment of the present invention. The force actuator 108may include a top cover 631 (not shown in FIG. 32) and a bottom cover632. Teeth 105 on the star gear 102 may pass between the top cover 631and the bottom cover 632 as the star gear 102 rotates. The top cover 631is removed and not shown in FIG. 32 for illustrative purposes.

The force actuator 108 may include a pivot point 641 and two rods 642and 643. The force actuator 108 pivots about the pivot point 641 due tomovement of the star gear 102. As the star gear 102 rotates, the teeth105 engage and disengage the first rod 642. In this regard, when a tooth105 comes in contact with the first rod 642, the tooth 105 pressesagainst the first rod 642, and the first rod 642 slides along theleading edge of the tooth 105 as the gear 102 rotates causing the forceactuator 108 to pivot about the pivot point 641 thereby causing thesecond rod 643 to push the pull arm 111 in the x-direction. Accordingly,the pull arm 111 rotates about the pivot point 214. This motion causesthe trigger 125 to move. In this regard, as the trigger 125 is pulled inthe x-direction by the pull arm 111, a spring 133 coupled to the trigger125 is stretched. Once the first rod 642 slides past the peak of thetooth 105, the force applied to the force actuator 108 by the star gear102 is decreased allowing the trigger's spring 133 to pull the trigger125 in the direction opposite of the x-direction. This trigger 125movement forces the pull arm 111 in the direction opposite of thex-direction, as well, causing the first rod 642 to slide along thetrailing edge of the tooth 105 until the first rod 642 contacts andslides along the leading edge of the next tooth 105.

The force actuator 108 and pull arm 111 operate essentially the sameregardless of the direction of rotation of the star gear 102. Thus, thetrigger 125 is repeatedly actuated as the door 52 is both opening andclosing. The opening of the door 52 rotates the star gear 102 in onedirection and the closing of the door 52 rotates the star gear 102 inthe opposite direction. In either case, as noted previously, the trigger125 is actuated and the generator 294 harnesses energy from the trigger125 movement to generate power.

FIGS. 33A and 33B show diagrams of a top view of a star gear and a pullarm in a home position and an associated position of a trigger,respectively according to an exemplary embodiment of the presentinvention.

FIGS. 34A and 34B show diagrams of a top view of a star gear and a pullarm in a maximum rotation position and an associated position of atrigger, respectively according to an exemplary embodiment of thepresent invention.

FIGS. 35-38 show diagrams of the trigger 125 and gear train 242 assemblyaccording to an exemplary embodiment of the present invention. Thetrigger 125 may include a plurality of tabs 701 and 702. The first tab701 may be coupled to the spring 133. The trigger 125 also may have twobolts 711 and 713 that pass through and are guided by slots 717 and 719(FIG. 38). In particular, the second bolt 713 passes through and isguided by a slot 717, and the first bolt 711 passes through and isguided by a slot 717 and 719 (FIG. 38).

FIG. 38 shows a diagram of the assembly of FIG. 37 from a side viewperspective according to an exemplary embodiment of the presentinvention. Various components, such as the slot 719, which are hiddenfrom view in FIG. 35 are shown in dashed lines in FIG. 38 forillustrative purposes. The slot 719 may be curved, and an end of theslot 719 may slope downward. A movable element 707 may have two bolts723 and 725 that pass through and are guided by a slot 727. When thetrigger 125 is forced in the x-direction by the pull arm 111, the secondtab 702 presses against a third tab 705 of the movable element 707 andmoves the element 707 in the x-direction.

FIGS. 39 and 40 show diagrams of the gear train 242 according to anexemplary embodiment of the present invention. The gear train 242includes a plurality of gears. One gear 733 has an internal clock spring735 (as shown in FIG. 40). The bolts 723 and 725 of the movable element707 are coupled to a rack 742, which has teeth 745 that engage teeth(not shown) of the gear 733. As the movable element 707 is in thex-direction by the trigger 125, the rack 745 moves in the x-directionalong with the element 707 thereby rotating the gear 733. This rotationof the gear 733 loads the clock spring 735. As described above and shownin FIG. 37, the slot 719 through which the bolt 711 passes is slopeddownward at one end. When the bolt 711 enters this sloped area of theslot 719, the end of the trigger 125 closest to the second tab 702 islowered such that the second tab 702 disengages the third tab 705 of themovable element 707. At this point, the force applied to the element 707by the trigger 125 is removed, and the element 707 is released from thetrigger 125. When this occurs, force from the clock spring 735, whichhas been loaded by movement of the rack 742 in the x-direction, spinsthe gear 733 until the tension in the spring 735 is exhausted. Therotation of the gear 733 is translated through the gear train 242 to thegenerator 294, which harnesses such energy thereby providing anelectrical pulse. In embodiments according to the present invention, aclutch mechanism may be used to ensure that the generator 294 receives,from the gear train 242, energy for rotating the generator 294 in onlyone direction. The generator may be any type of generator that mayaccomplish this task such as, for example, a generator with a rotatingelectromagnet that rotates from rotation of the gear train 242 andgenerates electrical power based on the rotation of the rotatingelectromagnet.

After the movable element 707 is released by the trigger 125 such thatthe element 707 is rapidly forced in the direction opposite of thex-direction by the loaded clock spring 735, a peak of the star geartooth 105 (FIG. 32) in contact with the first rod 642 passes the firstrod 642 thereby reducing the force exerted by the star gear 102 on theforce actuator 108 and ultimately the pull arm 111. Thus, the tension inthe spring 133 begins to pull the trigger 125 in the direction oppositeof the x-direction.

As the trigger 125 moves in the direction opposite of the x-direction,the second tab 702 contacts third tab 705 pushing the end of the movableelement 707 closest to the first bolt 723 upward such that the movableelement 707 pivots about the second bolt 725 in a clockwise directionrelative to the view seen by FIG. 35. Such pivoting allows the secondtab 702 to pass the third tab 705 as the trigger 125 moves in thedirection opposite of the x-direction. A torsion spring 763 resists thepivoting movement and generally applies a downward pressure on the bolt723 when the bolt 723, along the end of the element 707 closest to bolt723, are lifted by the second tab 702. Thus, once the second tab 702passes the third tab 705 as the trigger 125 is moving the directionopposite of the x-direction, the spring 763 forces the first bolt 723downward such that the movable element 707 pivots about the second bolt725 in the counter-clockwise direction thereby returning the third tab705 into the path of the second tab 702, the position shown by FIG. 35.Accordingly, when the next star gear tooth 105 contacts the forceactuator 108 moving the pull arm 111 in the x-direction, both thetrigger 125 and the movable element 707 are pulled in the x-direction asdescribed above, and the afore described process is repeated in order togenerate another electrical pulse.

Moreover, the process of actuating and releasing the movable element 707is continually repeated as long as the door 52 is moving therebygenerating a series of electrical pulses. These pulses are used tocharge an energy storage device such as, for example, a capacitor orbattery (not shown), which provides a continuous supply of electricalpower to electrical components of the door closer assembly 50 until theenergy storage device has lost all power (e.g., capacitor isdischarged). In one exemplary embodiment, a capacitor may be coupled toa voltage regulator (not shown), which regulates the voltage of thecapacitor such that the voltage is constant as long as there issufficient electrical power available to maintain the regulated voltage.

FIG. 41 shows a gear train 242 in a door closer 60 according to anexemplary embodiment of the present invention. The gear train 242 mayinclude one or more gears 326, 321, 102. An intermediate gear 321 may becoupled to an arm gear 326 and a star gear 102. The end of the pinion 66passes through a hole 604 in the star gear 102. The end of the pinion 66fits snugly through the hole 604 such that the star gear 102 rotates inunison with the end of the pinion 66. The star gear 102 has teeth 607that engage teeth 611 of the intermediate gear 321. Further, the armgear 326 has teeth 616 that engage a second set of teeth 622 of theintermediate gear 321. When the star gear 102 rotates due to rotation ofthe pinion 66, the intermediate gear 321 rotates due to the interactionof the intermediate gear teeth 611 and the star gear teeth 607. Inaddition, when the intermediate gear 321 rotates, the arm gear 326rotates due to the interaction of the arm gear teeth 616 and the secondset of teeth 622 of the intermediate gear 321. Thus, any rotation of thepinion 66 causes a corresponding rotation of the arm gear 326. In oneembodiment, the pinion 66 rotates at a ratio of 6 to 1 relative to thearm gear 326. For example, for 6 degrees of rotation of the pinion 66,the arm gear may rotate 1 degree. However, other ratios are possible inother embodiments according to the present invention.

Moreover, as shown in FIG. 41, at least one magnet 333′ is mounted onthe arm gear 326, and at least one magnetic sensor 236 is mounted on theprinted circuit board (PCB) 79. Note that the PCB 79 is removed fromFIG. 41 for illustrative purposes. The magnetic sensor 236 isstationary, and the magnet 333′ moves with the arm gear 326. Thus, anymovement by the door 52 causes a corresponding movement by the magnet333′ relative to the sensor 236. The control software logic 280 may beconfigured to determine a value indicative of the magnetic fieldstrength sensed by the sensor 336′ and to map such value to the door'sangular position. Further, as described above, the control software 280may be configured to use the door's 52 angular position to adjust thevalve's angular position to control the force generated by the closer50. An exemplary operation and use of the door closer assembly 50 isdescribed in more detail following.

To help illustrate embodiments according to the present invention,assume that it is desirable for the door closer assembly 50 to controlthe hydraulic force generated by the door closer assembly 50 during dooropening based on two door angles, referred to hereafter as “thresholdangles,” of 50 degrees and 70 degrees. In this regard, assume that thedoor closer assembly 50 is to generate a first hydraulic force resistiveof the door motion during opening for door angles less than 50 degrees.Between 50 and 70 degrees, the door closer assembly 50 is to provide agreater hydraulic force resistive of the door motion. For door anglesgreater than 70 degrees, the door closer assembly 50 is to provide a yetgreater hydraulic force resistive of the door motion. Further assumethat during closing, the door closer assembly 50 is to generate anotherhydraulic force for door angles greater than 15 degrees and a smallerhydraulic force for door angles equal to or less than 15 degrees.

FIG. 42 shows a block diagram of a control unit 64 printed circuit board79 for controlling a valve 100 of a door closer according to anexemplary embodiment of the present invention. The PCB 79 may include aprocessing element 555, a memory 582, control logic 583, a regulator545, an energy storage device 525, and an electrical interface 589. Theprocessing element 555, the memory 582, the control logic 583, and theelectrical interface 589 may be interconnected via a local interface bus588. The electrical interface 589 provides an interface for componentson the PCB 79 to a drive unit 62. The drive unit 62 may beinterconnected to a valve 100 via a cut-off screw 170. The control logic583 may include various types of electronic components and maycommunicate with the processing element 555 and the memory 582 and mayoperate together with the control software 80 and/or the processingelement 555 during control operations. In this regard, during discussionof embodiments of the present invention, if control software 580 ismentioned as performing a task, the control logic 583 may also beinvolved. Similarly, if the control logic 583 is mentioned as performinga task, the control software 580 may also be involved.

The memory 582 may contain information used in controlling a valve foroperation of a door such as, for example, valve position data 301, thecontrol software 580, and threshold data 377. The threshold data 377includes desired opening and closing characteristics for the door 52.For example, the threshold data 377 may indicate the door angles and thedesired angular position of the valve 69 for each door angle range. Inparticular, the data 377 may indicate that the angular position of thevalve 69 is to be at one position, referred to hereafter as the“high-flow position,” when the door angle is 50 degrees or less duringopening. The data 377 may also indicate that the angular position of thevalve 69 be at another position, referred to hereafter as the“medium-flow position,” when the door angle is greater than 50 degreesbut less than or equal to 70 degrees during opening. The threshold data377 may further indicate that the angular position of the valve 69 is tobe at yet another position, referred to hereafter as the “low-flowposition,” when the door angle is greater than 70 degrees duringopening. The medium-flow position allows a lower flow rate than thatallowed by the high-flow position, and the low-flow position allows alower flow rate than that allowed by the medium-flow position. Thus,using the above threshold data 377, the hydraulic forces generated bythe closer 60 resisting door movement should be at the highest above adoor angle of 70 degrees and at the lowest below a door angle of 50degrees. In addition, for illustrative purposes the threshold data 377may also indicate that, when the door is closing, the angular positionof the valve is to be at the medium-flow position for angles above 15degrees and at the low-flow position for angles less than or equal to 15degrees. According to embodiments of the present invention, thethreshold data 377 that includes the door opening threshold data and thedoor closing threshold data may be changed as desired by a user. Forexample, the threshold data 377 may be customized based on anenvironment that the door exists 52 in, or based on the nature of peopleopening and closing the door. The stored threshold data 377 may beprogrammed and changed by the use of selectors 999 on the exterior ofthe door closer assembly 50.

For illustrative purposes, assume that the door 52 is initially closedand a user pushes the door 52 to an angle of 80 degrees in order to walkthrough the doorway. Responsive to the door 52 opening, the generator294 begins to generate electrical power, which powers electronics in thecontrol unit 64. For example, the processing element 555 begins apower-up process upon receiving electrical power above a threshold andthen may begin to execute the control software 580 in the memory 582.Upon execution by the processing element 555 the control software 580determines the angular position of the valve 100 based on the magneticsensor 299. In this regard, the control software 580 may enable thesensor 299 and take a reading of the sensor 299. The control software580 then maps the sensor reading to the valve's angular position usingthe stored valve position data 301. In the instant example, assume thatthe valve 69 is initially set to the high-flow position.

The control software 580 may also determine the door angle based on thesensor 336′ residing on the arm gear 326. Assume that at this firstreading of the sensor 336′ the door angle is less than 50 degrees as thedoor 52 has just started opening. The control software 580 determineswhether the valve's angular position is to be adjusted. In this regard,the control software 580 determines whether the door 52 is opening orclosing based on the door angle. If the door angle is increasing, thenthe control software 580 determines that the door 52 is opening. If thedoor angle is decreasing, the control software 580 determines that thedoor 52 is closing. In the instant example, the door 52 is opening, andthe door angle is increasing.

The control software 580 accesses the threshold data 377 based on thecurrent angle of the door 52, to determine the appropriate valve 100position. In the instant example, the door angle is less than 50 degreesand the door is opening. Therefore, the control software 580 determinesthat the valve 100 should be set to the high-flow position. In addition,the control software 580 determines, based on the valve's currentangular position, that no adjustment is needed since the valve 100 isalready at the appropriate position.

Moreover, according to embodiments of the present invention, power issaved by the control software 580 determining whether to transition to apower-off state. In one exemplary embodiment, such a decision may bebased on the amount of electrical power that is available to continuepowering the electrical components of the door closer assembly 50. Thereare various techniques that can be used to determine the amount of powerthat is currently available. In one embodiment, an energy storage devicesuch as, for example, a capacitor or a battery, (not shown) may bemounted on the PCB 79 and charged by energy from the generator 294.Using a capacitor for the energy storage device for illustration, thecontrol software 580 may monitor the amount of charge stored by thecapacitor. When the charge stored by the capacitor falls below apredefined threshold, the control software 580 may determine that it istime to transition to a power-off state. In such a case, the controlsoftware 580 transitions the processing element 555 to a power-offstate. For example, the control software 580 may cause the processingelement 555 to power down so that no further power is drawn by theprocessing element 555 until the door 52 is later moving thereby causingthe generator 294 to generate power and restarting the process. Inaddition, according to embodiments of the present invention, duringoperation any of the electrical components, including the processingelement 555, may be shut down or transitioned to a sleep state in orderto conserve electrical power.

The control software 580 may take another reading of the door angle andrepeat the process until the control software 580 determines that thedoor angle has increased above 50 degrees. When this occurs, the controlsoftware 580 accesses the threshold data 377 and may determine that thevalve 100 should be in the medium-flow position, assuming that the doorangle is still less than 70 degrees. Since the valve 100 is currently inthe high-flow position, the control software 580 determines that thevalve position should be adjusted. The control software 580 may causethe processing element 555 to transmit a signal (e.g., a pulse widthmodulation (PWM) signal), to the motor 194, sufficient for causing themotor 194 to drive the cut-off screw 170 such that the valve's positionis transitioned from the high-flow position to the medium-flow position.As a result, the valve 100 restricts its flow rate such that the forcegenerated by the door closer assembly 50 for resisting the movement ofthe door 52 is increased.

If desired, the control software 580 may cause the processing element555 take additional readings of the valve sensor 299 to assist withcontrol of the motor 194 and/or to ensure that the cut-off screw 170 isrotated to put the valve 100 in the appropriate position. In thisregard, readings of the door sensor 336 and the valve sensor 299 may becontinuously periodically taken while power is available and the valveposition adjusted accordingly. The processor may be put into a sleepmode for a period to conserve power between cycles of reading the doorsensor 336 and the valve sensor 299. Further, once the position of thedoor 52 is read from the door sensor 336, it may be desired to onlyrepeatedly read the valve sensor 299 to insure the correct position ofthe valve 100. Also, since additional readings of the valve sensor 299increase power requirements, it may be desirable to adjust the angularposition of the valve 100 without any additional readings of the valvesensor 299.

When the door angle exceeds 70 degrees, the control software 580determines that the valve position is to be adjusted to the low-flowposition. Accordingly, the control software 580 causes the processingelement 555 to control the motor 194 such that the cut-off screw 170 isrotated causing the valve 100 to transition to the low-flow position.Therefore, the hydraulic force generated by the door closer assembly 50and resisting the movement of the door 52 is further increased.

Assume that, at some point, the door 52 is released or stopped and notopening. When this occurs, one or more springs in the door closerassembly 50, which were loaded as the door 52 was being opened, may nowgenerate a sufficient force to start closing the door 52 therebydecreasing the door angle. In such a state, the hydraulic forcegenerated by the door closer assembly 50 may counteract the forcegenerated by the one or more springs, which are closing the door 52.Upon sensing closing of the door 52 based on door angles read from thedoor sensor 336, the control software 580 determines that the valveposition is to be adjusted to the medium-flow position. Accordingly, thecontrol software 580 causes the processing element 555 to control themotor 194 such that the cut-off screw 170 is rotated causing the valve100 to transition to the medium-flow position. Therefore, the hydraulicforce generated by the door closer assembly 50 resisting the movement ofthe door 52 is decreased.

When the door angle falls below 15 degrees during closing, the controlsoftware 580 determines that the valve position is to be adjusted to thehigh-flow position. Accordingly, the control software 580 causes theprocessing element 555 to control the motor 264 such that the cut-offscrew 170 is rotated causing the valve 69 to transition to the high-flowposition. Therefore, the hydraulic force generated by the door closerassembly 50 and resisting the movement of the door 52 is furtherdecreased.

Once the door 52 fully closes, the generator 294 no longer receivespower since the door 52 is no longer moving. Thus, the generator 294stops generating power. Power may still be stored in the energy storagedevice 525 from the recent door movement. Eventually, the controlsoftware 580 determines that the available power from the energy storagedevice 525 has significantly decreased and makes the determination totransition the processing element 555 (and possibly other elements inthe control unit 64) to a power-off state. The processing element 555remains in a power-off state until the door 52 is later moved, (such aswhen the door is again opened) thereby causing power to be provided tothe processing element 555 from the generator 294 and energy storagedevice 525 and restarting the process of reading the door sensor 336(i.e., angular position of the door), the valve sensor 299 (i.e.,angular position of the valve), and adjusting the angular position ofthe valve 100 accordingly.

FIG. 43 shows a diagram of a circuit for conserving power in a doorcloser assembly 50 according to an exemplary embodiment of the presentinvention. The circuit may include the generator 294 coupled to theenergy storage device 525 where both may be coupled to a regulator 545and control logic 583. The control logic 583 may be connected to a motor194 and may include a microprocessor 555. In this exemplary embodiment,the processor 555 is shown as being a part of the control logic 583.Further, the processor 555 contains memory for storing the controlsoftware 580 and also includes a timer function 563. Embodiments of thepresent invention are not limited to this design as the control software580 and the timer 563 may reside outside of the processor 555 and/oroutside of the control logic 583.

As noted previously, according to embodiments of the present invention,to further help conserve power, the control software 580 monitors theamount of power that is available and takes various actions based on theamount of available power. In this regard, an energy storage device 525may be coupled to the generator 294 via a diode 527. To help illustrateembodiments of the present invention a capacitor is shown as the energystorage device. As noted previously, when a tooth 105 of the star gear102 disengages from the activator 108 allowing the spring 133 to movethe trigger 125 rapidly in a direction opposite of the x-direction FIG.33A-34B, the generator 294 generates an electrical pulse. As long as thedoor 52 continues moving, the generator 294 repetitively generateselectrical pulses since the trigger 125 is being actuated again andagain.

Each electrical pulse from the generator 294 charges the capacitor 525.Further, the capacitor 525 discharges over time between pulses.Accordingly, if the door 52 is moving fast enough, electrical power iscontinually delivered to control logic 283 during such movement.Further, a voltage regulator 545 may be coupled to the capacitor 525 andregulate the capacitor voltage so that this voltage is constant. This isprovided that there is sufficient power available to maintain theconstant voltage. For example, in one embodiment according to thepresent invention, the regulator 545 may regulate the voltage acrosscapacitor 525 to a particular voltage, for example, 3 volts. Thus, aslong as the capacitor 525 is sufficiently charged, the regulator 545keeps the voltage across capacitor 525 equal to 3 volts. However, if thedoor stops moving, thereby stopping the generation of electrical pulsesby the generator 294, then the voltage across capacitor 525 eventuallyfalls below 3 volts as the capacitor 525 starts to discharge.

According to embodiments of the present invention, the control logic 583may include a microprocessor 555. Further, at least a portion of thecontrol software 580 may be implemented in software and run on themicroprocessor 555. The timer 563 in the microprocessor 555 may beconfigured to generate an interrupt at certain times, as will bedescribed in more detail hereafter.

The parameters on which decisions are made to adjust valve position maychange relatively slowly compared to the speed of a typicalmicroprocessor. In this regard, a typical microprocessor is capable ofdetecting parameters that have a rate of change on the order of a fewmicroseconds. A longer time period may likely occur between changes tothe state of the valve position. To help conserve power, the controlsoftware 580 may be configured to transition the microprocessor 555 to asleep state after checking the valve sensor 299 and the door sensor 336and adjusting the valve position based on these readings, ifappropriate.

Before transitioning the microprocessor 555 to the sleep state, thecontrol software 580 may first set the timer 563 to expire a specifiedamount of time (e.g., 100 milliseconds) after the transition of themicroprocessor 555 to the sleep state. When the timer 563 expires, thetimer 563 generates an interrupt, causing the microprocessor 555 toawaken from its sleep state. Upon awakening, the control software 580may check the valve sensor 299 and the door sensor 336 and adjust thevalve position based on these readings, if appropriate. Thus, accordingto embodiments of the present invention, the microprocessor 555 mayrepetitively enter and exit a sleep state thereby saving electricalpower while the microprocessor 555 is in a sleep state. Moreover, inembodiments according to the present invention, other components of thecontrol logic 583 may similarly be transitioned into and out of a sleepstate, if desired.

In one exemplary embodiment, the control software 580 may monitor thevoltage across the capacitor 525 to determine when to perform an orderlyshut-down of the control logic 583 and, in particular, themicroprocessor 555. In this regard, the control software 580 may beconfigured to measure the voltage across the capacitor 525 and tocompare the measured voltage to a predefined threshold voltage level,referred to hereafter as the “shut-down threshold.” In one embodiment,the shut-down threshold may be established such that it is lower thanthe regulated voltage but within the acceptable operating voltage forthe microprocessor 555. In this regard, many microprocessors 555 have aspecified operating range for supply voltage to the microprocessor 555.If the microprocessor 555 is operated outside of this range, then errorsare likely. Thus, the shut-down threshold may be established such thatit is equal to or slightly higher than the lowest acceptable operatingvoltage of the microprocessor 555, according to the microprocessor'sspecifications as indicated by its manufacturer. It may also be possiblefor the shut-down threshold to be set lower than such minimum voltage,but doing so may increase the risk of error.

If the measured voltage falls below the shut-down threshold, then thecapacitor 525 has likely discharged to the extent that continuedoperation in the absence of another electrical pulse from the generator294 is undesirable. In such case, the control software 580 may initiatean orderly shut-down of the control logic 583 and, in particular, themicroprocessor 555 such that continued operation of the microprocessor555 at voltages outside of the desired operating range of themicroprocessor 555 is prevented. Once the shut-down of themicroprocessor 555 is complete, the microprocessor 555 no longer drawselectrical power.

In addition, the control software 580 may be configured to take otheractions based on the measured voltage of the capacitor 525. For example,in one embodiment according to the present invention, the controlsoftware 580 may be configured to delay or prevent an adjustment ofvalve position based on the measured voltage of the capacitor 525. Inthis regard, as the capacitor 525 discharges, the measured voltage(which is indicative of the amount of available power remaining) mayfall to a level that is above the shut-down threshold but neverthelessat a level for which the shut-down threshold will likely be passed if anadjustment of valve position is allowed and performed. Performing anadjustment of the valve position may consume a relatively large amountof electrical power compared to other operations, such as reading thevalve sensor 299 and the door sensor 336. As noted previously, to changethe valve position, the motor 194 may be actuated such that the cut-offscrew 170 is driven to an appropriate position in order to effectuate adesired valve position change. If the voltage of the capacitor 525 isclose to the shut-down threshold before a desired valve positionadjustment, then the power usurped by the motor 194 in effectuating thevalve position adjustment may cause the voltage of the capacitor 525 tofall significantly below the shut-down threshold.

To prevent the capacitor 525 voltage from falling significantly belowthe shut-down threshold, the control software 580 may compare themeasured voltage of the capacitor 525 to a threshold, referred tohereafter as the “delay threshold,” before initiating a valve positionchange. The delay threshold may be lower than the regulated voltage buthigher than the shut-down voltage. The delay threshold is preferablyselected such that, if it is exceeded prior to a valve positionadjustment, then the power usurped to perform a valve positionadjustment is not likely to cause the capacitor 525 voltage to fallsignificantly below the shut-down threshold.

If the measured voltage of the capacitor 525 is below the delaythreshold but higher than the shut-down threshold, then the controlsoftware 580 may wait before initiating the valve position adjustmentand continue monitoring the capacitor's 525 voltage. If an electricalpulse is generated by the generator 294 before the shut-down thresholdis reached, then the electrical pulse should charge the capacitor 525and, therefore, raise the voltage of the capacitor 525. If the measuredvoltage increases above the delay threshold, then the control software580 may initiate the valve position adjustment. However, if the measuredvoltage eventually falls below the shut-down threshold, then the controlsoftware 580 may initiate an orderly shut-down of the circuitry 540 and,in particular, the microprocessor 555 without performing the valveposition adjustment.

FIG. 44 shows a flowchart of a process for self-powered operation of adoor closer 60 according to an exemplary embodiment of the presentinvention. In the process 400, in block 401 a control unit 64 in a doorcloser assembly 50 is powered up from movement of a door 52. In block402 an angular position of the door 52 is read. In block 403 an angularposition of a valve 100 is read. In block 404 it may be determined ifthe valve 100 is to be adjusted and if so, then in block 405 the angularposition of the valve 100 may be adjusted and in block 406 a processor555 transitioned to a power saving sleep state. If the valve 100 is notto be adjusted then in block 406 the processor may be transitioned to apower saving sleep state. Then in block 407 it may be determined whethera sleep timer 563 has expired and if not the process loops on block 407and waits for the timer to expire. If the sleep time has expired then inblock 408 the processor 555 may be restored to an active state and theprocess repeat where in block 402 the angular position of the door 52 isagain read. The process may repeat while the control logic 582 and theprocessor 555 have power thus continually adjusting the angular positionof the valve 100, if needed, based on the angular position of the door52.

FIG. 45 shows a flowchart of a process for self-powered operation of adoor closer 60 according to another exemplary embodiment of the presentinvention. In this example embodiment, power to the valve sensor 299 andthe door sensor 336 are enabled only to take readings from these sensorsand then they are disabled. In the process 500, initially certainparameters used in the process may be setup. For example, in block 501 await timer value may be set, in block 502 a sleep timer value may beset, in block 503 a processor shutdown threshold may be set, and inblock 504 a valve adjust threshold may be set. These parameters may beused in different parts of the process.

In response to movement of a door 52, power may be generated. In block505 control circuitry in a door closer 60 may receive power generatedfrom movement of the door 52 and thus be powered up. In block 506, powerto a door sensor 336 may be enabled and a wait timer 563 started. Thewait timer 563 may be set with a value that allows time for an accuratesensor reading. In block 507 it may be determined if the wait timer 563has expired and if not, the process continues to make thisdetermination. If the wait timer 563 has expired then in block 508 anangular position of the door 52 may be read. In block 509 power to thedoor sensor 336 may be disabled.

In block 510, power to a valve sensor 299 may be enabled and the waittimer 563 started. The wait timer 563 may be set with a value thatallows time for an accurate sensor reading. In block 511 it may bedetermined if the wait timer 563 has expired and if not, the processcontinues to make this determination. If the wait timer 563 has expiredthen in block 512 an angular position of the valve 100 may be read. Inblock 513 power to the valve sensor 299 may be disabled. In block 514 itmay be determined if the position of the valve 100 needs to be adjusted.If the position of the valve 100 does need adjusting, then in block 515it may be determined if the remaining power level is larger than a valveadjust threshold, and if not then in block 516 it may be determined ifthe remaining power level is larger than the processor shutdownthreshold, and if not then in block 517 the processor 555 may be shutdown and powered off. If the remaining power level is larger than theprocessor shutdown threshold, then the process returns to block 515 todetermine if the remaining power level is larger than the valve adjustthreshold.

If the remaining power level is larger than the valve adjust threshold,then in block 518 the angular position of the valve 100 may be adjusted.If the valve position is not to be adjusted (block 514) or afteradjusting the angular position of the valve 100 then in block 519 it maybe determined if the remaining power level is larger than the processorshutdown threshold and if not, then in block 517 the processor 555 maybe shut down and powered off. If the remaining power level is largerthan the processor shutdown threshold, then in block 521 the processor555 may then be transitioned to a power saving sleep state. In block 522it may be determined if a sleep timer 563 has expired and if not, theprocess 555 may keep checking. If the sleep timer 563 has expired, thenan interrupt may be generated to the processor 555 and in block 523 theprocessor 555 may be restored an active state. Then the process mayreturn to block 506 where power to the door sensor 336 may be enabledand the wait timer 563 started, and the process repeated.

FIG. 46 shows a flowchart of a process for processing a door movementaccording to an exemplary embodiment of the present invention. In theprocess 650, in block 651 a first angular position of a door 52 is read.This may occur after movement of the door 52 is detected resulting incontrol logic 580 being powered up. In block 652 a second angularposition of the door 52 may be read. In block 653 the first angularposition of the door 52 and the second angular position of the door 52may be compared. In block 654 it may be determined if the differencebetween the two door positions is larger than a defined threshold and ifnot, in block 661 the valve position may be determined to be correct andnot need adjustment.

If the difference between the two door positions is larger than thedefined threshold, then in block 655 it may be determined whether thedoor 52 is opening or closing. If the door 52 is opening, the in block656 opening mode threshold data may be retrieved, whereas if the door 52is closing then in block 657 closing mode threshold data may beretrieved. The opening mode threshold data and the closing modethreshold data contain information regarding desired valve positionsrelative to angular positions of the door 52. In block 658 the desiredvalve position may be determined from the threshold data. In block 659the current actual valve position may be measured. In block 660 it maybe determined if the desired valve position is the same as the actualvalve position and if so, then in block 661 the valve position may bedetermined to be correct and not need adjustment. If the desired valveposition is not the same as the actual valve position, then in block 662the valve position may require adjustment.

An initial position of a door 52 may be determined by reading an angularposition of the door 52 (i.e., door angle). For example, the controllogic 580 may take a reading of the door sensor 336 to determine a doorangle, referred to hereafter as the “initial door angle.” After theinitial reading, the control logic 580 takes another reading of the doorsensor 336 to determine a second door angle, referred to hereafter asthe “current door angle.” The control logic 580 then compares the twodoor angles. For example, the control logic 580 may subtract the currentdoor angle from the initial door angle. The control logic 580 maycompare the absolute value of the difference between the two door anglesto a predefined threshold, referred to hereafter as the “hysteresisthreshold”. The hysteresis threshold may be selected such that it is notexceeded if the door 52 is stationary (e.g., closed) or is moving tosuch a small degree such that adjusting the valve position isundesirable.

For example, a user may have opened the door 52 and be holding the door52 open at substantially the same angle. Thus, the user is notattempting to further close or open the door 52 but is rather attemptingto hold the door 52 open at a constant angle. However, minute changes inthe door angle may nevertheless occur as the user is attempting to holdthe door 52 at a substantially constant angle. Without a degree ofhysteresis, the control logic 580 might otherwise change itsdetermination as to whether to operate in an opening mode or a closingmode and therefore needlessly adjust the valve position many times whilethe user is holding the door 52 open. Such adjustments not only usurpelectrical power but also may increase wear on the components used toadjust the valve position. Thus, the hysteresis threshold may beselected to provide a desired level of hysteresis for the determinationas to whether the closer 60 should operate in the opening mode orclosing mode.

If the hysteresis threshold is not exceeded, then the control logic 580may determine that no adjustment of the valve position is to beperformed. However, if the hysteresis threshold is exceeded, then thecontrol logic 580 may further consider whether a valve positionadjustment is to be performed. In this regard, based on the sign of thedifference between the two door angles subtracted, the control logic 580may determine whether the door 52 is opening or closing and, therefore,whether the control logic 580 should operate in the opening mode or theclosing mode. If the initial door angle is greater than the current doorangle, then the control logic 580 may determine that the door 52 isclosing and that the control logic 580 should operate in the closingmode. If the initial door angle is less than the current door angle,then the control logic 603 may determine that the door is opening andthat the control logic 580, therefore, should operate in the openingmode.

Depending on the mode of operation, the control logic 580 may retrieve asubset of the threshold data 377. In particular, the control logic 580may retrieve the portion of the data 377 that is to be compared to theangular position of the valve 69 read for the selected mode ofoperation. In this regard, if in the closing mode, then the controllogic 580 retrieves the data to be used to select the desired valveposition when the door is closing whereas, if in the opening mode, thecontrol logic 580 retrieves the data to be used to select the desiredvalve position when the door is opening. Based on the current doorangle, the control logic 580 determines the desired valve position, asindicated by the retrieved data 377. The control logic 580 may alsodetermine whether the actual position of the valve 69 matches thedesired valve position. If so, the control logic 580 may determine thatno valve position adjustment is to be performed. If not, the logic 580determines that a valve position adjustment is to be performed andappropriately adjust the position of the valve 100, thereby changing thestate of the valve 100, so that the valve 100 is set to its desiredposition, assuming that the there is sufficient power available to makethe adjustment. Accordingly, a state (e.g., flow rate) of the valve 100is changed.

FIG. 47 shows a flowchart of a process for processing a door movementaccording to another exemplary embodiment of the present invention. Inthe process 800, in block 801 a control unit 64 is powered up frommovement of a door 52. In block 802 an angular position of the door 52is read and stored. In block 803 an angular position of the valve 100 isread and stored. In block 804 the currently read door position may becompared with the previously read door position. In block 805 a speed ofmovement of the door 52 may be calculated based on the comparison. Inblock 806 a next door movement may be predicted based on the calculateddoor speed and previously stored door speeds. In block 807 it may bedetermined whether an angular position of a valve 100 should be adjustedand if so, in block 808 the angular position of the valve 100 may beadjusted and in block 809 a processor 555 may be transitioned to a powersaving sleep state for a set period of time and then awakened. If theangular position of a valve 100 should not be adjusted then in block 809the processor 555 may be transitioned to a power saving sleep state fora set period of time and then awakened. The process may then repeat byreturning to block 802 where an angular position of the door 52 is againread and stored. Therefore, according to embodiments of the presentinvention, two successive door angles may be read, stored and comparedto determine a speed of movement of the door 52 and the speed used withother previously stored speeds to predict a next possible position ofthe door 52.

FIG. 48 shows a flowchart of a process for processing a door movementaccording to a still further exemplary embodiment of the presentinvention. In the process 900, in block 901 a first angular position ofa door 52 is read and stored. In block 902 a second angular position ofthe door 52 is read and stored. In block 903 the first door position maybe compared with the second door position. In block 904 a speed ofmovement of the door may be calculated based on the comparison. In block905 the door speed may be associated with the first door position andthe second door position and stored. In block 906 the stored door speedmay be compared to an average speed for the first door position and thesecond door position. The average speed may be a value that is anaverage of multiple previous speeds calculated and stored for the samefirst door position and same second door position. In block 907 it maybe determined whether an angular position of a valve 100 should beadjusted and if so, in block 908 the angular position of the valve 100may be adjusted and in block 909 the stored door speed may be averagedwith previously stored door speeds for the same first door position andsecond door position and stored and the process repeat to block 901where a first angular position of a door 52 is read and stored. If theangular position of a valve 100 should not be adjusted then in block 909the stored door speed may be averaged with previously stored door speedsfor the same first door position and second door position and stored andthe process repeat to block 901 where a first angular position of a door52 is read and stored. Therefore, according to embodiments of thepresent invention, an angular position of valve 100 may be adjustedbased on a door speed being compared to a stored average door speed thuspreventing inadvertent adjustment of the valve 100 based on an abnormalmovement of the door such as a sudden wind gust.

Although the present invention has been shown and described inconsiderable detail with respect to only a few exemplary embodimentsthereof, it should be understood by those skilled in the art that we donot intend to limit the invention to the embodiments since variousmodifications, omissions and additions may be made to the disclosedembodiments without materially departing from the novel teachings andadvantages of the invention, particularly in light of the foregoingteachings. For example, some of the novel features of the presentinvention could be used with any type of hydraulic door closer.Accordingly, we intend to cover all such modifications, omission,additions and equivalents as may be included within the spirit and scopeof the invention as defined by the following claims. In the claims,means-plus-function clauses are intended to cover the structuresdescribed herein as performing the recited function and not onlystructural equivalents but also equivalent structures. Thus, although anail and a screw may not be structural equivalents in that a nailemploys a cylindrical surface to secure wooden parts together, whereas ascrew employs a helical surface, in the environment of fastening woodenparts, a nail and a crew may be equivalent structures.

1. A door closer assembly, comprising: a valve, the valve regulating anamount of hydraulic fluid that flows through the valve, the amount ofhydraulic fluid flowing through the valve controlling a force generatedby the door closer assembly on a door; a first sensor, the first sensormeasuring an angular position of the door; a second sensor, the secondsensor measuring an angular position of the valve, the angular positionof the valve determining the amount of hydraulic fluid flowing throughthe valve; and a controller, the controller controlling the adjustmentof the valve based on the angular position of the door and the angularposition of the valve, wherein the controller reads a first angularposition of the door from the first sensor and then reads a secondangular position of the door from the first sensor, and the controllerdetermines a difference between the first angular position and thesecond angular position and compares the difference with a thresholdvalue.
 2. The door closer assembly according to claim 1, wherein thecontroller determines whether the door is opening or closing based onthe comparison and the difference between the first angular position andthe second angular position.
 3. The door closer assembly according toclaim 2, wherein the controller retrieves one of opening mode thresholddata or closing mode threshold data when the difference is above thethreshold value.
 4. The door closer assembly according to claim 3,wherein the controller controls the adjustment of the valve based on oneof the opening mode threshold data or the closing mode threshold data.5. The door closer assembly according to claim 3, wherein the openingmode threshold data and the closing mode threshold data define desiredvalve positions based on the measured angular position of the door. 6.The door closer assembly according to claim 5, wherein the controllermakes no adjustment of the valve when the difference is below thethreshold value.
 7. The door closer assembly according to claim 3,wherein the opening mode threshold data and the closing mode thresholddata are determined by settings on the exterior of the door closer.